1. Field of the Invention
The present invention generally relates to a programmable power measurement chip, and more particularly to universal power measurement chip architecture that external apparatuses can pre-setup required functions.
2. Description of the Prior Art
Power measurement circuits are applied in various measurement devices and industrial control apparatuses to convert analog power signals (such as voltage, current, . . . ) into digital power signals for further processing.
The architecture of the prior art of power measurement devices, such as voltmeters and ammeters, as shown in FIG. 1, includes a signal detector 1, an analog signal conditioner 2, an analog-to-digital converter 3, a micro controller 4, a power supply 5, a memory 6, a communication interface 7, and an LCD interface 8.
The signal detector 1 can convert physical (analog) signals into voltage signals. After the signal conditioner 2 adjusts the voltage signals into proper amplitude, the analog-to-digital converter 3 converts the adjusted analog signals into digital signals. The micro controller 4 processes the digital signals in accordance with the pre-setup programs. The processed power information can be saved in the memory 6, shown in the external LCD through the LCD interface 8, or directed to an external storage apparatus through the communication interface 7. The power supply 5 is a battery for a handhold meter, or a linear or switching power supply for built-in meter to supply the needed power for each circuit.
The mentioned prior art of the circuitry architecture is applied in a voltmeter, then the signal detector 1, analog signal conditioner 2, analog-to-digital converter 3, and programs in the micro controller 4 have to be designed for the characteristics of the voltage measurement. If the architecture is applied in the other power measurements, all the above circuitry and programs have to be redesigned. It lacks flexibility in application. Once the architecture is applied in a universal integrated power measurement apparatus, all of the desired signal detector 1, analog signal conditioner 2, and analog-to digital converter 3 have to be incorporated in a single system. Besides, if the micro controller 4 is designed to execute a variety of the power measurement programs, it is necessary to have a processing procedure to arrange the various programs properly to avoid the conflict of the execution. Consequently, the volume of the measurement apparatus is getting much bigger, and the hardware is getting more complicated to increase the chances of the interferences among the programs. Therefore, the prior art of the circuitry architecture is always a big burden for designers and manufacturers, because they have to design and manufacture the meters for each different use according to the need of the market, in no way to respond to the real-time requirement.